Each mobile telephone (“mobile phone”) is associated with a unique phone number. When a caller places a call from a mobile phone to a destination device, the unique phone number of the mobile phone can be transmitted to the destination device as an identifier. This feature is typically referred to as caller identification, or “Caller ID”.
A mobile phone is generally associated with a first service provider that sends and receives calls to and from the phone, and provides other messaging services to the mobile phone. The first service provider can also provide the mobile phone with access to a network of cellular base stations for sending and receiving calls. Many mobile phones can also be installed with software applications that extend the capabilities of the mobile phone. Some of these software applications offer telecommunication services (e.g. voice over internet protocol, text messaging) provided by a different service provider than the first service provider.